From 05795cb0034e885bec37f782cfc6bddcae262637 Mon Sep 17 00:00:00 2001
From: tmk <hasu@tmk-kbd.com>
Date: Wed, 26 Nov 2014 11:25:45 +0900
Subject: [PATCH] Compensate timer during prower down

---
 common/avr/suspend.c           | 27 ++++++++++++++++-----------
 common/suspend.h               |  2 +-
 keyboard/hhkb_rn42/MEMO.txt    |  7 +++++++
 keyboard/hhkb_rn42/matrix.c    |  2 +-
 keyboard/hhkb_rn42/rn42/main.c |  2 +-
 protocol/lufa/lufa.c           |  2 +-
 6 files changed, 27 insertions(+), 15 deletions(-)

diff --git a/common/avr/suspend.c b/common/avr/suspend.c
index 66a579fd7..80243f02b 100644
--- a/common/avr/suspend.c
+++ b/common/avr/suspend.c
@@ -7,6 +7,7 @@
 #include "backlight.h"
 #include "suspend_avr.h"
 #include "suspend.h"
+#include "timer.h"
 #ifdef PROTOCOL_LUFA
 #include "lufa.h"
 #endif
@@ -52,11 +53,13 @@ void suspend_idle(uint8_t time)
  *          WDTO_4S
  *          WDTO_8S
  */
-void suspend_power_down(uint8_t wdto)
+static uint8_t wdt_timeout = 0;
+static void power_down(uint8_t wdto)
 {
 #ifdef PROTOCOL_LUFA
     if (USB_DeviceState == DEVICE_STATE_Configured) return;
 #endif
+    wdt_timeout = wdto;
 
     // Watchdog Interrupt Mode
     wdt_intr_enable(wdto);
@@ -67,7 +70,6 @@ void suspend_power_down(uint8_t wdto)
     // - prescale clock
     // - BOD disable
     // - Power Reduction Register PRR
-
     set_sleep_mode(SLEEP_MODE_PWR_DOWN);
     sleep_enable();
     sei();
@@ -78,6 +80,11 @@ void suspend_power_down(uint8_t wdto)
     wdt_disable();
 }
 
+void suspend_power_down(void)
+{
+    power_down(WDTO_15MS);
+}
+
 bool suspend_wakeup_condition(void)
 {
     matrix_power_up();
@@ -103,15 +110,13 @@ void suspend_wakeup_init(void)
 /* watchdog timeout */
 ISR(WDT_vect)
 {
-    /* wakeup from MCU sleep mode */
-/*
-    // blink LED
-    static uint8_t led_state = 0;
-    static uint8_t led_count = 0;
-    led_count++;
-    if ((led_count & 0x07) == 0) {
-        led_set((led_state ^= (1<<USB_LED_CAPS_LOCK)));
+    // compensate timer for sleep
+    switch (wdt_timeout) {
+        case WDTO_15MS:
+            timer_count += 15 + 2;  // WDTO_15MS + 2(from observation)
+            break;
+        default:
+            ;
     }
-*/
 }
 #endif
diff --git a/common/suspend.h b/common/suspend.h
index f339c670a..80617a824 100644
--- a/common/suspend.h
+++ b/common/suspend.h
@@ -6,7 +6,7 @@
 
 
 void suspend_idle(uint8_t timeout);
-void suspend_power_down(uint8_t timeout);
+void suspend_power_down(void);
 bool suspend_wakeup_condition(void);
 void suspend_wakeup_init(void);
 
diff --git a/keyboard/hhkb_rn42/MEMO.txt b/keyboard/hhkb_rn42/MEMO.txt
index 337dad603..062ee3399 100644
--- a/keyboard/hhkb_rn42/MEMO.txt
+++ b/keyboard/hhkb_rn42/MEMO.txt
@@ -9,10 +9,15 @@ Bug:
     - Do not power-down during USB connection is active - DONE 11/11
         (USB_DeviceState == USB_DEVICE_Configured) is used to check USB connection
         matrix_power_down() matrix.c - 11/23
+- timer is slow while power down - DONE 11/26
+    - time out interrupt is lost while power down?
+    - interrupt of watchdog timer compensates timer counter(avr/suspend.c)
 
 Todo:
 
 Design:
+- suspend.h - DONE 11/26
+    - remove argument from suspend_power_down() for backward compatitibility
 - remove MCU dependent power saving code from core/keyboard
     - it should be located in project matrix.c - DONE 11/23
 - HHKB matrix.c needs matrix_prev?
@@ -47,6 +52,8 @@ Power saving:
 - During USB suspend change clock source to internal RC from external Xtal(6.8)
 - FRZCLK: you can freeze clock for power saving. still WAKEUPI and VBUSTI interrupts are available while freezing.(21.7.3)
 - Suspend: Clear Suspend Bit, Freeze clock, disable PLL, MCU sleep(21.13)
+- Voltage reference(8.1.1)
+    - to reduce power consumption while power down mode
 
 Improving:
 - BT LED; connecting, linked, sleeping, deep sleeping
diff --git a/keyboard/hhkb_rn42/matrix.c b/keyboard/hhkb_rn42/matrix.c
index c6c444ff5..513a271e4 100644
--- a/keyboard/hhkb_rn42/matrix.c
+++ b/keyboard/hhkb_rn42/matrix.c
@@ -186,6 +186,6 @@ void matrix_power_down(void) {
     if (USB_DeviceState == DEVICE_STATE_Configured) return;
     if (timer_elapsed32(matrix_last_modified) <= MATRIX_POWER_SAVE) return;
     KEY_POWER_OFF();
-    suspend_power_down(WDTO_15MS);
+    suspend_power_down();
     matrix_power = false;
 }
diff --git a/keyboard/hhkb_rn42/rn42/main.c b/keyboard/hhkb_rn42/rn42/main.c
index 43d887067..a3a37c074 100644
--- a/keyboard/hhkb_rn42/rn42/main.c
+++ b/keyboard/hhkb_rn42/rn42/main.c
@@ -85,7 +85,7 @@ int main(void)
     print("Keyboard start.\n");
     while (1) {
         while (USB_DeviceState == DEVICE_STATE_Suspended) {
-            suspend_power_down(WDTO_120MS);
+            suspend_power_down();
             if (USB_Device_RemoteWakeupEnabled && suspend_wakeup_condition()) {
                     USB_Device_SendRemoteWakeup();
             }
diff --git a/protocol/lufa/lufa.c b/protocol/lufa/lufa.c
index 6802f3b63..ee15b7f45 100644
--- a/protocol/lufa/lufa.c
+++ b/protocol/lufa/lufa.c
@@ -587,7 +587,7 @@ int main(void)
     print("Keyboard start.\n");
     while (1) {
         while (USB_DeviceState == DEVICE_STATE_Suspended) {
-            suspend_power_down(WDTO_120MS);
+            suspend_power_down();
             if (USB_Device_RemoteWakeupEnabled && suspend_wakeup_condition()) {
                     USB_Device_SendRemoteWakeup();
             }